Stimulus, recording and subject factors influencing ABR diagnostic criteria

If the diagnostic potential of ABR is to be fully realised, then diagnostic criteria applicable in any clinic and with any equipment are needed. The factors, which may vary between clinics and which can influence the value of a diagnostic criterion, are considered and evaluated. The variables in stimulation and recording parameters and the patient variables which must be taken into consideration in order to achieve internationally applicable standards are detailed. Using the I-V interpeak interval as an example of a parameter for which an international standard may be formulated, the effects of both physical and subject variables and the interactions which they show are given. The interactions between these parameters can account for many of the differences found between different clinics and laboratories. The normative data required by each clinic are outlined and suggestions which could lead to an international standard are made.